Silicon Micro-electromechanical Systems (MEMS) pressure sensors, using Wheatstone bridges formed by piezoresistive resistance elements, are common in the marketplace. Many of these Silicon pressure sensors use Silicon on Insulator (SOI) technology, which utilizes a thin layer of SiO2 (often referred to as a Silica glass) to isolate a substrate from the piezoresistive resistance elements. While this allows operation at temperatures up to 300 C for MEMS based piezoresistive silicon pressure sensors, high accuracy performance is limited by mechanical interaction between the SiO2 layer and the silicon pressure sensor diaphragm. Specifically, long term stability and high accuracy for high pressure sensors that operate above 150 C at >10 KSI are problematic due to non-correctable drifts in sensor output caused by subjecting the SiO2 layer to high pressures under high temperature conditions.
For the reasons stated above and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the specification, there is a need in the art for systems and methods that address the SiO2 layer's impact on performance and stability at high temperatures and high pressures.